1. Field of the Invention
The present invention relates to a socket for an electric part and particularly, to a socket for an electric part for electrically connecting terminals of the electric part to a printed wiring board of a measurer in order to carry out a performance test for the electric part.
2. Description of the Related Art
In order to carry out a performance test for an electric part such as a semiconductor device and the like, a socket for an electric part for electrically connecting terminals of the electric part to a printed wiring board of a measurer is conventionally used in many cases.
In such a socket for an electric part, a top plate is disposed on a socket body and designed, so that the electric part is placed on the top plate. Contact pins are disposed on the socket body, and a slide plate is disposed between the top plate and the socket body for sliding movement in a horizontal direction. Further, an upper operating member for moving the slide plate is disposed for vertical movement relative to the socket body.
Thus, the slide plate is slid horizontally through a levering mechanism or a link mechanism by lowering the upper operating member, thereby resiliently deforming the contact pins to spread upper ends of the contact pins. Thereafter, the electric part is placed on the top plate, and the slide plate is moved back to the original position by lifting the upper operating member, thereby releasing an urging force on the contact pins. This causes the contact pins to be returned to their initial positions by their resilient forces, whereby the terminals of the electric part are clamped by the tip ends of the contact pins and electrically connected to the contact pins.
However, the conventional socket for the electric part suffers from the following problem: The slide plate is slid horizontally through the link mechanism or the like by lowering the upper operating member and for this reason, it is necessary to turn the downward urging force into a horizontal direction perpendicular to an urging direction and hence, a large force for urging the upper operating member is required. Another problem is that a large force is also required for returning the upper operating member and hence, it is necessary to ensure an increased biasing force of a spring or the like for returning the upper operating member, resulting in an increase in cost of parts.
Accordingly, it is an object of the present invention to provide a socket for an electric part, wherein the slide plate can be moved easily by urging the upper operating member by a small force.
To achieve the above object, according to a first aspect and feature of the present invention, there is provided a socket for an electric part, comprising a socket body, a plurality of contact pins disposed on the socket body and capable of being connected to and disconnected from terminals of an electric part, a slide plate movably disposed on the socket body, and an upper operating member, so that the slide plate is moved by the upper operating member, thereby opening and closing tip ends of the contact pins to connect the contact pins to the terminals of the electric part, wherein said socket further include a support lever disposed for turning movement about a base end, and the slide plate is attached to the support lever, so that the slide plate is moved laterally and downwards by urging the upper operating member downwards.
With the above arrangement, the slide plate is moved laterally and downwards by urging the upper operating member downwards. Therefore, the slide plate can be moved easily only by urging the upper operating member by a small force. In addition, because the support lever is turned, less frictional force is produced in the turning movement of the support lever. Therefore, it is possible to suppress a loss of energy during the turning movement to the utmost and hence, the support lever can be turned by a smaller force.
According to a second aspect and feature of the present invention, in addition to the first feature, the socket further includes an urging member disposed on the upper operating member for urging the support lever, so that the support lever is turned by urging the upper operating member downwards.
With the above arrangement, the support lever is turned by urging the upper operating member downwards and hence, the support lever can be turned easily.
According to a third aspect and feature of the present invention, in addition to the first feature, the slide plate is attached to the support lever through a support shaft, and the socket further includes an urging member disposed on the upper operating member for urging the support lever, so that the support lever is turned through the support shaft by urging the upper operating member downwards.
With the above arrangement, the support lever is turned through the support shaft by urging the upper operating member downwards and hence, the support lever can be turned easily. Moreover, a frictional force produced during the urging can be decreased, and the upper operating member can be turned by a smaller force.
According to a fourth aspect and feature of the present invention, in addition to any of the first to third features, a plurality of the support levers are mounted at diagonal portions of the slide plate, respectively, so that the slide plate is moved laterally and downwards, i.e., in a diagonal direction by turning the support levers.
With the above arrangement, the slide plate is moved laterally and downwards, i.e., in a diagonal direction by turning the support levers by turning the support levers by urging the upper operating member downwards. Therefore, the support levers can be turned easily to move the slide plate.
According to a fifth aspect and feature of the present invention, in addition to the fourth feature, the contact pins are disposed obliquely in parallel to the diagonal direction, so that a direction of spreading of the contact pins coincides with a direction of movement of the slide plate.
With the above arrangement, the contact pins are disposed obliquely in parallel to the diagonal direction, so that the direction of spreading of the contact pins coincides with the direction of movement of the slide plate. Therefore, a large space in the direction of spreading of the contact pins can be ensured, and even when the contact pins 3 are disposed more closely, the spreading movements of the contact pins 3 can be conducted reliably, and it is possible to easily accommodate an increase in density of an electric part in recent years.
The above and other objects, features and advantages of the invention will become apparent from the following description of the preferred embodiment taken in conjunction with the accompanying drawings.